And as I was considering, behold, a male goat came from the west on the face of the whole earth, and touched not the ground: and the goat had a notable horn between his eyes.
All Commentaries on Daniel 8:5 Go To Daniel 8
Jerome
AD 420
On the basis of the previous visions which had symbolized the second kingdom by the ram and the he-goat, Daniel now also understood that he was looking at the empire of the Medes and Persians.